Question why captured stream comes in 5 minute chunks

[jimdagys]

Using Orbit, I captured a stream from
http://www.cctv.com/program/e_dialogue/01/index.shtml
In the past , when I used Orbit, I could capture the whole 30 minute program a few minutes with one file. However, this time (see Screenshot) I had to play most of the 30 minute program, and every 5 minutes, a new file would appear in the Orbit download. After all files appeared, I clicked download, and then got six 5 minute chunks that had to be joined. I used Avidemux (as set in screenshot) to join and convert to regular avi. (File >open and then Append subsequent files). My question is:
Why did this capture come in six 5 minute chunks instead of 1 file?

[jagabo]

To make your life difficult.